8,353 research outputs found

    Chemical characteristics and nutritive values of three oat varieties for ruminants

    Get PDF
    Non-Peer ReviewedThe objectives of this study were to determine the magnitude of differences among oat varieties of in terms of detailed chemical and nutritional characteristics (including: 1) chemical composition, 2) total digestible nutrient (TDN) and energy values at maintenance and production level for both dairy and beef cattle, 3) protein and carbohydrate subfractions, 4) in situ degradation kinetics of components, and 5) nutrient supply/availability) and provide detailed feeding values for ruminants. Six oat samples comprised of 3 cultivars (CDC Dancer, Derby and CDC SO-I) grown over two years (2005 and 2006) were obtained from the Crop Development Centre at the University of Saskatchewan. The samples were analyzed for DM, CP, EE, GE, starch, ash, NDF, ADF, ADL, NDICP, ADICP, SCP and NPN. Total digestible nutrient (TDN) and energy values (TDN1x, DE3x, ME3x, NEL3x, DE4x, ME4x, NEL4x of dairy, ME, NEm and NEg of beef) at maintenance and production levels for both dairy and beef cattle were determined using NRC-2001 and NRC-1996 chemical approaches. Protein and carbohydrate fractions were determined using the CNCPS system. Rumen degradation kinetics (DM, CP and starch) were determined in situ. The nutrient supply/availability will be estimated using the DVE/OEB system and NRC-2001 model. Detailed chemical composition, TDN and energy values and CNCPS protein and carbohydrate fractions are reported here. The information obtained from this study will be useful for oat breeders and feed industry

    Nuclear charge-exchange excitations in localized covariant density functional theory

    Get PDF
    The recent progress in the studies of nuclear charge-exchange excitations with localized covariant density functional theory is briefly presented, by taking the fine structure of spin-dipole excitations in 16O as an example. It is shown that the constraints introduced by the Fock terms of the relativistic Hartree-Fock scheme into the particle-hole residual interactions are straightforward and robust.Comment: 4 pages, 1 figure, Proceedings of INPC2013, Florence, Italy, 2-7 June 201

    Coordinate shift in the semiclassical Boltzmann equation and the anomalous Hall effect

    Full text link
    We propose a gauge invariant expression for the side jump associated with scattering between particular Bloch states. Our expression for the side jump follows from the Born series expansion for the scattering T-matrix in powers of the strength of the scattering potential. Given our gauge invariant side jump expression, it is possible to construct a semiclassical Boltzmann theory of the anomalous Hall effect which expresses all previously identified contributions in terms of gauge invariant quantities and does not refer explicitly to off-diagonal terms in the density-matrix response.Comment: 6 pages, 1 fugure. submitted to PR

    Joint beamforming design for secure RIS-assisted IoT networks

    Get PDF
    This paper studies secure communication in an internet-of-things (IoT) network, where the confidential signal is sent by an active refracting reconfigurable intelligent surface (RIS)-based transmitter, and a passive reflective RIS is utilized to improve the secrecy performance of users in the presence of multiple eavesdroppers. Specifically, we aim to maximize the weighted sum secrecy rate by jointly designing the power allocation, transmit beamforming (BF) of the refracting RIS, and the phase shifts of the reflective RIS. To solve the non-convex optimization problem, we propose a linearization method to approximate the objective function into a linear form. Then, an alternating optimization (AO) scheme is proposed to jointly optimize the power allocation factors, BF vector and phase shifts, where the first one is found using the Lagrange dual method, while the latter two are obtained by utilizing the penalty dual decomposition method. Moreover, considering the demands of green and secure communications, by applying the Dinkelbach’s method, we extend our proposed scheme to solving a secrecy energy maximization problem. Finally, simulation results demonstrate the effectiveness of the proposed design

    Temperature dependence of electron-spin relaxation in a single InAs quantum dot at zero applied magnetic field

    Full text link
    The temperature-dependent electron spin relaxation of positively charged excitons in a single InAs quantum dot (QD) was measured by time-resolved photoluminescence spectroscopy at zero applied magnetic fields. The experimental results show that the electron-spin relaxation is clearly divided into two different temperature regimes: (i) T < 50 K, spin relaxation depends on the dynamical nuclear spin polarization (DNSP) and is approximately temperature-independent, as predicted by Merkulov et al. (ii) T > about 50 K, spin relaxation speeds up with increasing temperature. A model of two LO phonon scattering process coupled with hyperfine interaction is proposed to account for the accelerated electron spin relaxation at higher temperatures.Comment: 10 pages, 4 figure

    Singular Effects of Spin-Flip Scattering on Gapped Dirac Fermions

    Full text link
    We investigate the effects of spin-flip scattering on the Hall transport and spectral properties of gapped Dirac fermions. We find that in the weak scattering regime, the Berry curvature distribution is dramatically compressed in the electronic energy spectrum, becoming singular at band edges. As a result the Hall conductivity has a sudden jump (or drop) of e2/2he^2/2h when the Fermi energy sweeps across the band edges, and otherwise is a constant quantized in units of e2/2he^2/2h. In parallel, spectral properties such as the density of states and spin polarization are also greatly enhanced at band edges. Possible experimental methods to detect these effects are discussed

    Effects of Plasmonic Metal Core - Dielectric Shell Nanoparticles on the Broadband Light Absorption Enhancement in Thin Film Solar Cells

    Get PDF
    To guide the design of plasmonic solar cells, theoretical investigation of core (metal)-shell (dielectric) nanoparticles for light absorption enhancement in thin film Si solar cells is performed. In contrast to the reported simulations and experimental results that rear-located surface plasmon on bare metallic nanoparticles is preferred, the core-shell nanoparticles demonstrate better performance when surface plasmon is located in front of a solar cell. This has been attributed to the enhanced forward scattering with vanishing backward scattering preserved over a wide spectral range in core-shell nanoparticles. This work provides a concept to achieve enhanced forward scattering with weakened backward scattering in plasmonic thin film solar cells
    • …
    corecore